pizza@debian:~/c$ cat /proc/cpuinfo
processor       : 0
vendor_id       : GenuineIntel
cpu family      : 6
model           : 15
model name      : Intel(R) Core(TM)2 CPU         T7200  @ 2.00GHz
stepping        : 8
cpu MHz         : 1995.519
cache size      : 64 KB
fdiv_bug        : no
hlt_bug         : no
f00f_bug        : no
coma_bug        : no
fpu             : yes
fpu_exception   : yes
cpuid level     : 10
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss nx pni ds_cpl
bogomips        : 3907.58

pizza@debian:~/c$ time ./perfect-square speed 4294967295
checking [0,4294967295]...
done.

real    28m36.339s
user    28m18.278s
sys     0m8.828s